Audio Test Tone Generator

Professional quality sound signal generator for audio engineers to test equipment using their AndroidTM device.

Multiple wave forms: Sine, Triangle, Square and Sawtooth.

Custom frequency selection from 2 Hz to 20 kHz.

Frequency Sweep.

Noise: White, Pink and Brown.

All signals are generated in real-time and the application can run in the background.

A setting allows you to decide whether the tone generator should automatically stop when you receive an incoming call. Hence the only special permission the App requires on your device is the ability to determine whether you're on a call or not (READ_PHONE_STATE).

Help documentation is built in to the App (no network access is required).

Requires Android OS version 2.3.3 or later.

Available now on Google's Android Market priced at 4.99 GBP.

Listed under Multimedia apps or use this QR code. Larger QR code is at the bottom of this page.

By default a 'damage warning' is displayed each and every time you press the Play button. This warning can be disabled in the Settings once you get used to how the application works.

Output is 16 bit, mono and is rendered at the highest sample rate supported by Android on the device (typically 44100 Hz).

Level Adjustment and Calibration

A couple of users have been in touch to request the ability to either apply a digital pad to the output level or to be able to calibrate the output level.

The software currently outputs the wave forms at the maximum peak to peak amplitude that can be generated in 16 bit samples without clipping. Output level can only be set using the 'Media volume' control provided by the Android device. It is up to the device manufacturer as to how they implement this in respect of both hardware (DAC and possibly VCA) and software (audio driver). For this reason the scale is neither accurate or defined!

We are considering adding calibration to the software but are working on how to do it cleanly. If you have thoughts in this respect then please get in touch.